Retrieve file size or last modified date of an external file in SAS
Retrieve file size or last modified date of an external file – The FINFO functions return the value of a file specified. You can get six attributes named ‘info items’ through the use of the FINFO function.
Data Step Technique to Retrieve file size or last modified date of an external file
data a(drop=fid); infile fileref truncover obs=1; fid=fopen('fileref'); Bytes=finfo(fid, 'File Size (bytes)'); crdate=finfo(fid, 'Create Time'); moddate=finfo(fid, 'Last Modified'); run; |
Macro Technique Retrieve file size or last modified date of an external file
%macro FileAttribs(filename); %local rc fid fidc; %local Bytes CreateDT ModifyDT; %let rc=%sysfunc(filename(file, &filename)); %let fid=%sysfunc(fopen(&file)); %let Bytes=%sysfunc(finfo(&fid, File Size (bytes))); %let CreateDT=%qsysfunc(finfo(&fid, Create Time)); %let ModifyDT=%qsysfunc(finfo(&fid, Last Modified)); %let fidc=%sysfunc(fclose(&fid)); %let rc=%sysfunc(filename(file)); %put NOTE: File size of &filename is &Bytes bytes; %put NOTE- Created &CreateDT; %put NOTE- Last modified &ModifyDT; %mend FileAttribs; /** Just pass in the path and file name **/ %FileAttribs(/home/sasExamples/demo.sas) |
Here is the output of the below code.
NOTE: File size of /home/subhroster20070/choosec.sas is 429 bytes Created Last modified 01 February 2021 11:23:23 |
Retrieve file size or last modified date of an external file for Multiple Files in a directory
To read multiple within a directory, the DOPEN, DNUM and DREAD functions can be used.
The DOPEN function is similar to the FOPEN function and it returns a directory identifier that allows the directory to be opened for input.
The DNUM function counts the number of files within the opened location. You can use this to loop through all the files in a location.
DREAD is used to read each file within the directory. This makes each file accessible for the FOPEN and FINFO functions.
data fileinfo (keep=filename1 filepath Bytes moddate); filename files '/home/subhroster20070/examples'; dirid=dopen('files'); countfiles=dnum(dirid); do i=1 to countfiles; filename1=dread(dirid, i); filepath='/home/subhroster20070/examples/'||filename1; sysrc=filename('fnames'||left(i), filepath); exist=pathname('fnames'||left(i)); fid=fopen('fnames'||left(i)); Bytes=finfo(fid, 'File Size (bytes)'); moddate=finfo(fid, 'Last Modified'); sysrc=filename('fnames'); output; sysrc=close(fid); end; rc=dclose(dirid); run; |
Very nice articles and well explained.
Very useful!!. Thanks